NOTCH activation promotes valve formation by regulating the endocardial secretome

Torregrosa-Carrión, R., Luna-Zurita, L., García-Marqués, F., D'Amato, G., Piñeiro-Sabarís, R., Bonzón-Kulichenko, E., Vázquez, J., de la Pompa, J.L.
Molecular & cellular proteomics : MCP   18(9): 1782-1795 (Journal)
Registered Authors
de la Pompa, José Luis
Cardiovascular function or biology, Developmental biology*, EMT, Endocardium, NOTCH, RNA SEQ, Secretome, Signal Transduction*, cardiac valve
MeSH Terms
  • Adaptor Proteins, Signal Transducing/genetics
  • Adaptor Proteins, Signal Transducing/metabolism
  • Animals
  • Benzazepines/pharmacology
  • Calcium-Binding Proteins/genetics
  • Calcium-Binding Proteins/metabolism
  • Cells, Cultured
  • Endocardium/cytology
  • Endocardium/drug effects
  • Endocardium/embryology*
  • Endocardium/metabolism*
  • Extracellular Matrix/metabolism
  • Gene Expression Regulation, Neoplastic
  • Heart Valves/embryology*
  • Heart Valves/metabolism
  • Intercellular Signaling Peptides and Proteins/metabolism
  • Jagged-1 Protein/genetics
  • Jagged-1 Protein/metabolism
  • Mice, Mutant Strains
  • Receptor, Notch1/genetics
  • Receptor, Notch1/metabolism
  • Receptors, Notch/genetics
  • Receptors, Notch/metabolism*
  • Reproducibility of Results
31249105 Full text @ Mol. Cell. Proteomics
The endocardium is a specialized endothelium that lines the inner surface of the heart. Functional studies in mice and zebrafish have established that the endocardium is a source of instructive signals for the development of cardiac structures, including the heart valves and chambers. Here, we characterized the NOTCH-dependent endocardial secretome by manipulating NOTCH activity in mouse embryonic endocardial cells (MEEC) followed by mass spectrometry-based proteomics. We profiled different sets of soluble factors whose secretion not only responds to NOTCH activation, but also shows differential ligand specificity, suggesting that ligand-specific inputs may regulate the expression of secreted proteins involved in different cardiac development processes. NOTCH signaling activation correlates with a TGFβ2-rich secretome and the delivery of paracrine signals involved in focal adhesion and extracellular matrix (ECM) deposition and remodeling. In contrast, NOTCH inhibition is accompanied by the upregulation of specific semaphorins that may modulate cell migration. The secretome protein expression data showed a good correlation with gene profiling of RNA expression in embryonic endocardial cells. Additional characterization by in situ hybridization in mouse embryos revealed expression of various NOTCH candidate effector genes (Tgfβ2, Loxl2, Ptx3, Timp3, Fbln2 and Dcn) in heart valve endocardium and/or mesenchyme. Validating these results, mice with conditional Dll4 or Jag1 loss-of-function mutations showed gene expression alterations similar to those observed at the protein level in vitro. These results provide the first description of the NOTCH-dependent endocardial secretome and validate MEEC as a tool for assaying the endocardial secretome response to a variety of stimuli and the potential use of this system for drug screening.
Genes / Markers
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Engineered Foreign Genes